TSM Channel Self Calibration Capacitive Touch Sensor SPECIFICATION V1.0

Transcription

1 TSM2 2-Channel Self Calibration Capacitive Touch Sensor SPECIFICATION V.0

2 Specification TSM2 (2-CH Auto Sensitivity Calibration Capacitive Touch Sensor). General Feature 2-Channel capacitive sensor with auto sensitivity calibration Selectable output operation (single mode / multi-mode) Independently adjustable in 8 step sensitivity Sync function for multi chip application Touch intensity can be detectable within 3 steps (Low, Middle and High) Adjustable internal frequency with external resister Adjustable response time and interrupt level by the control registers I2C serial interface Embedded high frequency noise elimination circuit IDLE mode to save the consumption Embedded power key function on channel for mobile phone application RoHS compliant 32QFN package.2 Application Mobile application (mobile phone / PDA / PMP etc) Membrane switch replacement Sealed control panels, keypads Door key-lock matrix application Touch screen replacement application.3 Package (32QFN) TSM2 32QFN (Drawings not to scale)

3 2 Pin Description (32QFN) PIN No. Name I/O Description Protection RBIAS Analog Input Internal bias adjust input /GND 2 SRBIAS Analog Input IDLE Mode Internal bias adjust input /GND 3 CS5 Analog Input CH5 capacitive sensor input /GND 4 CS6 Analog Input CH6 capacitive sensor input /GND 5 CS7 Analog Input CH7 capacitive sensor input /GND 6 CS8 Analog Input CH8 capacitive sensor input /GND 7 CS9 Analog Input CH9 capacitive sensor input /GND 8 N.C. - No Connection - 9 CS0 Analog Input CH0 capacitive sensor input /GND 0 Digital Input - /GND CS Analog Input CH capacitive sensor input /GND 2 CS2 Analog Input CH2 capacitive sensor input /GND 3 VSS Ground Supply ground 4 NC - No Connection - 5 IRBIAS Analog Input Internal I2C clk frequency adjust input /GND 6 RST Digital Input System reset (High reset) /GND 7 OUT Digital Output CH output (Open drain) /GND 8 SCL Digital Input I2C clock input /GND 9 SDA Digital Input/Output I2C data (Open drain) /GND 20 INT Digital Output Interrupt output (Open drain) /GND 2 I2C_EN Digital Input I2C enable(low enable) /GND 22 ID_SEL Digital Input I2C address selection /GND 23 P_CDEG0 Digital Input Ch sensitivity selection bit0 /GND 24 P_CDEG Digital Input Ch sensitivity selection bit /GND 25 P_CDEG2 Digital Input Ch sensitivity selection bit2 /GND 26 VSS Digital Input - /GND 27 SYNC/OPT Digital Input/Output Output mode selection (Single Output / Multi Output Note ) Sync pulse input /output /GND 28 Power Power (2.5V~5.0V) GND 29 CS Analog Input CH capacitive sensor input /GND 30 CS2 Analog Input CH2 capacitive sensor input /GND 3 CS3 Analog Input CH3 capacitive sensor input /GND 32 CS4 Analog Input CH4 capacitive sensor input /GND Note : Refer to 6.3 SYNC/OPT implementation 2

4 3 Absolute Maximum Rating Battery supply voltage 5.0V Maximum voltage on any pin +0.3 Maximum current on any PAD 00mA Power Dissipation 800mW Storage Temperature -50 ~ 50 Operating Temperature -20 ~ 75 Junction Temperature 50 Note Unless any other command is noted, all above are operated in normal temperature. 4 ESD & Latch-up Characteristics 4. ESD Characteristics Mode Polarity Max Reference 2000V H.B.M Pos / Neg 2000V VSS 2000V P to P 200V M.M Pos / Neg 200V VSS 200V P to P C.D.M Pos / Neg 500V 800V DIRECT 4.2 Latch-up Characteristics Mode Polarity Max Test Step I Test Positive Negative 200mA -200mA 25mA V supply over 5.0V Positive 8.0V.0V 3

5 5 Electrical Characteristics V DD =3.3V, Rb=50k, Sync Mode (Rsync = 2MΩ) (Unless otherwise noted), T A = 25 Characteristics Symbol Test Condition Min Typ Max Units Operating supply voltage V DD V V DD = 3.3V R B =50k R_SB= V DD = 5.0V R B =50k R_SB= I DD μa V DD = 3.3V R B =50k R_SB=3M Current consumption V DD = 5.0V R B =50k R_SB=3M Note V DD = 3.3V R B =50k R I2C =20k ma I DD_I2C V DD = 5.0V R B =50k R I2C =30k IDD_I2C Disable - - μa Output maximum sink current Sense input capacitance range Note2 Sense input resistance range Minimum detective capacitance difference Output impedance (open drain) Self calibration time after system reset Recommended bias resistance range Note3 I OUT T A = ma C S pf R S Ω ΔC Zo Cs = 0pF, C DEG = 200pF (I2C default sensitivity select) ΔC > 0.2pF, Cs = 0pF, (I2C default sensitivity select) ΔC < 0.2pF, Cs = 0pF, (I2C default sensitivity select) pf M - V DD = 3.3V R B = 50k T CAL V DD = 5.0V R B = 50k R B V DD = 3.3V V DD = 5.0V Maximum bias C B_MAX pf capacitance Recommended sync R SYNC 2 20 MΩ resistance range Note : In case of SCL frequency is 500kHz. Note 2 : The sensitivity can be increased with lower C S value. The recommended value of C S is 0pF when using 3T PC(Poly Carbonate) cover and 0 mm x 7 mm touch pattern. Note 3 : The lower R B is recommended in noisy condition. Ω ms kω 4

6 6 Implementation of TSM2 6. RBIAS & SRBIAS implementation RBIAS << C B R B SRBIAS << R SB The RBIAS is connecting to the resistor to decide the oscillator and internal bias current. The sensing frequency, internal clock frequency and current consumption are therefore able to be adjusted with R B. A voltage ripple on RBIAS can make critical internal error, so C B is connected to the (not GND) is recommended. (The typical value of C B is 820pF and the maximum Value is nf.) The R SB should be connected as above figure when the TSM2 operates in IDLE Mode to save the current consumption. In this case, the consumption depends on the sum of the serial resistors and the response time might be longer. I DD [ua] V 3.3 V 5.0 V R B [kω] Normal operation current consumption curve (Pin2 I2C_EN is High) The current consumption curve of TSM2 is represented in accordance with R B value as above. The lower R B requires more current consumption but it is recommended in noisy application. For example, refrigerator, air conditioner and so on. 5

7 6.2 CS implementation CS2 << R S2 Touch PAD8 C S2 CS << R S Touch PAD C S The TSM2 has basically eight steps sensitivity, which is available to control with internal register by I2C interface. The parallel capacitor C S is added to CS and C S2 to CS2 to adjust sensitivity. The sensitivity will be increased when smaller value of C S is used. (Refer to the below Sensitivity Example Figure) It could be useful in case detail sensitivity mediation is required. The internal touch decision process of each channel is separated from each other. The twelve channel touch key board application can therefore be designed by using only one TSM2 without coupling problem. The R S is serial connection resistor to avoid mal-function from external surge and ESD. (It might be optional.) From 200Ω to kω is recommended for R S. The size and shape of PAD might have influence on the sensitivity. The sensitivity will be optimal when the size of PAD is approximately an half of the first knuckle (it s about 0 mm x 7 mm ). The connection line of CS ~ CS2 to touch PAD is recommended to be routed as short as possible to prevent from abnormal touch detect caused by connection line. 6

8 Sensitivity example figure with default sensitivity selection 6.3 SYNC/OPT implementation 6.3. Output Mode Option This pin will be assigned for the output mode option selection. It will decide that TSM2 is working on single or multi touch detection mode. It should be implemented as below for these. SYNC/OPT << (Single Output Mode Implementation) SYNC/OPT << (Multi Output Mode Implementation) 7

9 6.3.2 Multi Chip Application Over two TSM2 can work on the one application at the same time thanks to SYNC function with this pin. The SYNC pulse prevents over two sensing signal from interfering with each other. R SYNC is pull-down resistor of SYNC/OPT pin. Too big value of R SYNC makes the SYNC pulse falling delay, and too small value of R SYNC makes rising delay. Typical value of R SYNC is 2MΩ.The Sync pin should be implemented as below. The TSM2 can also be used with the other TSxx series by employing this SYNC function. The TSM2 could only operate on multi output mode in this configuration. SYNC/OPT << st TSM2 R SYNC SYNC(/OPT)<< 2 nd TSM2 or TS** 6.4 P_CDEG2, P_CDEG, P_CDEG0 implementation The P_CDEG0, and 2 are only for the CS to control the sensitivity. The sensitivity of channel will be controlled by the register (refer to the sensitivity control register chapter) same as the other channel if the P_CDEG(2:0) value is 0. But it should be fixed as following table if the P_CDEG(2:0) value is not 0. The sensitivity table of channel P_CDEG(2:0) Sensitivity of Channel (@Cs = 0pF) 0 Respect the register value (refer to the I2C register description) 000 4~6T 00 2~4T 00 0~2T 00 7~9T 0 6~8T 0 5~7T 3~5T Note : The unit T represents the thickness (mm) of a panel in case of poly-carbonate. Note 2: The above table data is compatible with a pad size that is approximately an half of the first knuckle. (it s about 0 mm x 7 mm ) The channel provides the output with two ways whether the I2C or the out (pin7) directly. 8

10 6.5 RESET implementation TSM2 has internal data latches, so initial state of these latches must be reset by external reset pulse before normal operation starts. The reset pulse can be controlled by host MCU directly or other reset device. If not, the circuit should be composed as below figure. The reset pulse must have high pulse duration about a few msec to cover power rising time. The recommended value of R RST and C RST are 330KΩ and 00nF. C RST RESET << R RST Recommended reset circuits The better performance is warranted with below reset circuit. The Q is turned on and makes reset pulse when power is on and is raised to operating voltage. After a few msec (duration time is determined by R7, R8, C5), Q is turned off and TSM2 can be operated with normal sensitivity. R7 200K Q 2N3906 R8 200K RESET C5 220nF R9 470K Recommended reset circuits 2 9

11 7 I 2 C Interface 7. IRBIAS Implementation IRBIAS << R IB The R IB is only charged in making the I2C internal clock and should be implemented as above figure. The smaller R IB will increase the I2C internal clock frequency and current consumption. (Refer to the following consumption curve) I 2 C I DD [ua] I 2 C I DD Measure (RB = 50kΩ) = 3.3V = 5.0V R IB [kω] I2C Block operation current consumption curve 0

12 I 2 C Clk Freq. [MHz] 2.00 I 2 C Clk Freq. (RB = 50kΩ) = 3.3V 0.00 = 5.0V R IB [kω] I2C clock frequency curve 7.2 Start & Stop Condition Start Condition (S) Stop Condition (P) Repeated Start (Sr) The EN (Pin2) should be low before START condition and be high after STOP condition. EN

13 7.3 Data validity The SDA should be stable when the SCL is high and the SDA can be changed when the SCL is low. 7.4 Byte Format The byte structure is composed with 8Bit data and an acknowledge signal. 7.5 Acknowledge It is a check bit whether the receiver gets the data from the transmitter without error or not. The receiver will write 0 when it received the data successfully and if not. 2

14 7.6 First Byte 7.6. Slave Address It is the first byte from the start condition. It is used to access the slave device. ID_SEL GND TSM2 Chip Address : 7bit Address 0xD0 0xF R/W The direction of data is decided by the bit and it follows the address data. MSB LSB Address R/W 7 bit bit 3

15 7.7 Transferring Data 7.7. Write Operation The byte sequence is as follows: the first byte gives the device address plus the direction bit (R/W = 0). the second byte contains the internal address of the first register to be accessed. the next byte is written in the internal register. Following bytes are written in successive internal registers. the transfer lasts until stop conditions are encountered. the TSM2 acknowledges every byte transfer Read Operation The address of the first register to read is programmed in a write operation without data, and terminated by the stop condition. Then, another start is followed by the device address and R/W=. All following bytes are now data to be read at successive positions starting from the initial address Read/Write Operation 4

16 7.8 I 2 C write and read operations in normal mode The following figure represents the I 2 C normal mode write and read registers. Write register 0x00 to 0x0 with data AA and BB Start Device Address 0xD0 ACK Register Address 0x00 ACK Data AA ACK Data BB ACK Stop Read register 0x00 and 0x0 Start Device Address 0xD0 ACK Register Address 0x00 ACK Stop Start Device Address 0xD ACK Data Read AA ACK Data Read BB ACK Stop From Master to Slave From Slave to Master 5

17 8 TSM2 Register List Note: The unused bits (defined as reserved) in I²C registers must be kept to zero. Note: The bit0 and bit of CTRL2 register must be written by 0b after power on during an initialize phase. (Refer to the chapter 9. initialize flow) Note: HS (High Sensitivity) / MS (Middle Sensitivity) / LS (Low Sensitivity) Note: Low Output (light touch) / Middle Output (middle touch) / High Output (hard touch) 8. I 2 C Register Map Name Addr. (Hex) Reset Value Register Function and Description (Bin) Bit7 Bit6 Bit5 Bit4 Bit3 Bit2 Bit Bit0 Sensitivity 02h 0 0 Ch2HL Ch2M ChHL ChM Sensitivity2 03h 0 0 Ch4HL Ch4M Ch3HL Ch3M Sensitivity3 04h 0 0 Ch6HL Ch6M Ch5HL Ch5M Sensitivity4 05h 0 0 Ch8HL Ch8M Ch7HL Ch7M Sensitivity5 06h 0 0 Ch0HL Ch0M Ch9HL Ch9M Sensitivity6 07h 0 0 Ch2HL Ch2M ChHL ChM CTRL 08h MS FTC ILC RTC CTRL2 09h XX SRST IDLE Ref_rst 0Ah 0 Ch8 Ch7 Ch6 Ch5 Ch4 Ch3 Ch2 Ch Ref_rst2 0Bh Ch2 Ch Ch0 Ch9 Ch_hold 0Ch 0 Ch8 Ch7 Ch6 Ch5 Ch4 Ch3 Ch2 Ch Ch_hold2 0Dh Ch2 Ch Ch0 Ch9 Cal_hold 0Eh Ch8 Ch7 Ch6 Ch5 Ch4 Ch3 Ch2 Ch Cal_hold2 0Fh Ch2 Ch Ch0 Ch9 Output 0h OUT4 OUT3 OUT2 OUT Output2 h OUT8 OUT 7 OUT6 OUT5 Output3 2h OUT2 OUT OUT0 OUT9 6

18 8.2 Sensitivity Control Register Sensitivity Channel & 2 Sensitivity Control Address (hex): 02h Type: R/W Bit7 Bit6 Bit5 Bit4 Bit3 Bit2 Bit Bit0 Ch2HL Ch2M[2:0] ChHL ChM[2:0] Description The sensitivity of channel and 2 are adjustable by Sensitivity_ register. ChxM[2:0] allows various middle sensitivity and also the high and low sensitivities are decided with ChxHL. Bit name Reset Function Middle sensitivity T (= thickness of = 0pF ChxM[2:0] 0 ChxHL Sensitivity2 000: 4~6T 00: 2~4T 00: 0~2T 0: 08~0T 00: 7~9T 0: 6~8T 0: 5~7T : 3~5T High and Low sensitivity selection for channel x 0: HS = MS - (MS * 0.2) LS = MS + (MS * 0.2) : HS = MS - (MS * 0.3) LS = MS + (MS * 0.3) Channel 3 & 4 Sensitivity Control Address (hex): 03h Type: R/W Bit7 Bit6 Bit5 Bit4 Bit3 Bit2 Bit Bit0 Ch4HL Ch4M[2:0] Ch3HL Ch3M[2:0] Description The sensitivity of channel 3 and 4 are adjustable by Sensitivity_2 register. ChxM[2:0] allows various middle sensitivity and also the high and low sensitivities are decided with ChxHL. Bit name Reset Function Middle sensitivity T (= thickness of = 0pF ChxM[2:0] 0 ChxHL 000: 4~6T 00: 2~4T 00: 0~2T 0: 08~0T 00: 7~9T 0: 6~8T 0: 5~7T : 3~5T High and Low sensitivity selection for channel x 0: HS = MS - (MS * 0.2) LS = MS + (MS * 0.2) : HS = MS - (MS * 0.3) LS = MS + (MS * 0.3) 7

19 Sensitivity3 Channel 5 & 6 Sensitivity Control Address (hex): 04h Type: R/W Bit7 Bit6 Bit5 Bit4 Bit3 Bit2 Bit Bit0 Ch6HL Ch6M[2:0] Ch5HL Ch5M[2:0] Description The sensitivity of channel 5 and 6 are adjustable by Sensitivity_3 register. ChxM[2:0] allows various middle sensitivity and also the high and low sensitivities are decided with ChxHL. Bit name Reset Function Middle sensitivity T (= thickness of = 0pF ChxM[2:0] 0 ChxHL Sensitivity4 000: 4~6T 00: 2~4T 00: 0~2T 0: 08~0T 00: 7~9T 0: 6~8T 0: 5~7T : 3~5T High and Low sensitivity selection for channel x 0: HS = MS - (MS * 0.2) LS = MS + (MS * 0.2) : HS = MS - (MS * 0.3) LS = MS + (MS * 0.3) Channel 7 & 8 Sensitivity Control Address (hex): 05h Type: R/W Bit7 Bit6 Bit5 Bit4 Bit3 Bit2 Bit Bit0 Ch8HL Ch8M[2:0] Ch7HL Ch7M[2:0] Description The sensitivity of channel 7 and 8 are adjustable by Sensitivity_4 register. ChxM[2:0] allows various middle sensitivity and also the high and low sensitivities are decided with ChxHL. Bit name Reset Function Middle sensitivity T (= thickness of = 0pF ChxM[2:0] 0 ChxHL 000: 4~6T 00: 2~4T 00: 0~2T 0: 08~0T 00: 7~9T 0: 6~8T 0: 5~7T : 3~5T High and Low sensitivity selection for channel x 0: HS = MS - (MS * 0.2) LS = MS + (MS * 0.2) : HS = MS - (MS * 0.3) LS = MS + (MS * 0.3) 8

20 Sensitivity5 Channel 9 & 0 Sensitivity Control Address (hex): 06h Type: R/W Bit7 Bit6 Bit5 Bit4 Bit3 Bit2 Bit Bit0 Ch0HL Ch0M[2:0] Ch9HL Ch9M[2:0] Description The sensitivity of channel 9 and 0 are adjustable by Sensitivity_5 register.chxm[2:0] allows various middle sensitivity and also the high and low sensitivities are decided with ChxHL. Bit name Reset Function Middle sensitivity T (= thickness of = 0pF ChxM[2:0] 0 ChxHL Sensitivity6 000: 4~6T 00: 2~4T 00: 0~2T 0: 08~0T 00: 7~9T 0: 6~8T 0: 5~7T : 3~5T High and Low sensitivity selection for channel x 0: HS = MS - (MS * 0.2) LS = MS + (MS * 0.2) : HS = MS - (MS * 0.3) LS = MS + (MS * 0.3) Channel & 2 Sensitivity Control Address (hex): 07h Type: R/W Bit7 Bit6 Bit5 Bit4 Bit3 Bit2 Bit Bit0 Ch2HL Ch2M[2:0] ChHL ChM[2:0] Description The sensitivity of channel and 2 are adjustable by Sensitivity_6 register. ChxM[2:0] allows various middle sensitivity and also the high and low sensitivities are decided with ChxHL. Bit name Reset Function Middle sensitivity T (= thickness of = 0pF ChxM[2:0] 0 ChxHL 000: 4~6T 00: 2~4T 00: 0~2T 0: 08~0T 00: 7~9T 0: 6~8T 0: 5~7T : 3~5T High and Low sensitivity selection for channel x 0: HS = MS - (MS * 0.2) LS = MS + (MS * 0.2) : HS = MS - (MS * 0.3) LS = MS + (MS * 0.3) 9

21 8.3 General Control Register CTRL TSM2 General Control Register Address (hex): 08h Type: R/W Bit7 Bit6 Bit5 Bit4 Bit3 Bit2 Bit Bit0 MS FTC[:0] ILC[:0] RTC[2:0] Description The calibration speed just after power on reset is very high during the time which is defined by FTC[:0] to have a good adoption against unstable external environment. Bit name Reset Function MS 0 Mode Selection 0: auto alternate (fast/slow) mode : fast mode FTC[:0] 0 First Touch Control Below time stands on = 3V / Rb = 300KΩ 00: 5 sec 0: 0 sec 0: 5 sec : 20 sec ILC[:0] 00 Interrupt Level Control 00: Interrupt is on middle or high output. 0: Interrupt is on low or middle or high output. 0: Interrupt is on middle or high output. : Interrupt is on high output. RTC[2:0] 0 Response Time Control Response period = RTC[2:0]

22 8.4 General Control Register2 CTRL2 TSM2 General Control Register2 Address (hex): 09h Type: R/W Bit7 Bit6 Bit5 Bit4 Bit3 Bit2 Bit Bit SRST SLEEP Description All the digital blocks except analog and I2C block are reset when SRST is set. The SLEEP function allows getting very low current consumption when it is set. But the response time will be longer than normal operation. The bit0 and bit must be written with 0b by host MCU. Bit name Reset Function SRST 0 Software Reset 0: Disable Software Reset : Enable Software Reset SLEEP Sleep Mode Enable 0: Disable Sleep Mode : Enable Sleep Mode Bit[:0] XX These bits must be written by 0b during a system initialize phase. (refer to the chapter 9 initialize flow example ) 2

23 8.5 Channel Reference Reset Control Register Ref_rst Channel~8 Reference Reset Control Address (hex): 0Ah Type: R/W Bit7 Bit6 Bit5 Bit4 Bit3 Bit2 Bit Bit0 Ch8 Ch7 Ch6 Ch5 Ch4 Ch3 Ch2 Ch Description The reference value of each channel will be renewing when Chx is set. Bit name Reset Function Chx 0: Disable reference reset : Enable reference reset Ch 0 0: Disable reference reset : Enable reference reset Ref_rst2 Channel9~2 Reference Reset Control Address (hex): 0Bh Type: R/W Bit7 Bit6 Bit5 Bit4 Bit3 Bit2 Bit Bit Ch2 Ch Ch0 Ch9 Description The reference value of each channel will be renewing when Chx is set. Bit name Reset Function 0: Disable reference reset Chx : Enable reference reset 22

24 8.6 Channel ~8 Sensing Control Register Ch_hold Channel ~ 8 Hold Enable Register Address (hex): 0Ch Type: R/W Bit7 Bit6 Bit5 Bit4 Bit3 Bit2 Bit Bit0 Ch8 Ch7 Ch6 Ch5 Ch4 Ch3 Ch2 Ch Description The operation of each channel is independently available to control. A channel doesn t be worked and the calibration is paused when it is set. Bit name Reset Function Chx 0: Enable operation (sensing + calibration) : Hold operation (No sensing + Stop calibration) Ch 0 0: Enable operation (sensing + calibration) : Hold operation (No sensing + Stop calibration) 8.7 Channel 9~2 Sensing Control Register Ch_hold2 Channel 9 ~ 2 Hold Enable Register Address (hex): 0Dh Type: R/W Bit7 Bit6 Bit5 Bit4 Bit3 Bit2 Bit Bit Ch2 Ch Ch0 Ch9 Description The operation of each channel is independently available to control. A channel doesn t be worked and the calibration is paused when it is set. Bit name Reset Function CEx 0: Enable operation (sensing + calibration) : Hold operation (No sensing + Stop calibration) 23

25 8.8 Channel ~8 Calibration Control Register Cal_hold Channel ~ 8 Calibration Enable Register Address (hex): 0Eh Type: R/W Bit7 Bit6 Bit5 Bit4 Bit3 Bit2 Bit Bit0 Ch8 Ch7 Ch6 Ch5 Ch4 Ch3 Ch2 Ch Description The calibration of each channel is independently available to control. Each channel is working even if a bit is set. Bit name Reset Function Chx 0 0: Enable reference calibration (sensing + calibration) : Disable reference calibration (sensing + No calibration) 8.9 Channel 9~2 Calibration Control Register Cal_hold2 Channel 9 ~ 2 Calibration Enable Register Address (hex): 0Fh Type: R/W Bit7 Bit6 Bit5 Bit4 Bit3 Bit2 Bit Bit Ch2 Ch Ch0 Ch9 Description The calibration of each channel is independently available to control. Each channel is working even if a bit is set. Bit name Reset Function Chx 0 0: Enable reference calibration (sensing + calibration) : Disable reference calibration (sensing + No calibration) 24

26 8.0 Output Register Output Channel ~ 4 Output Register Address (hex): 0h Type: R Bit7 Bit6 Bit5 Bit4 Bit3 Bit2 Bit Bit0 OUT4[:0] OUT3[:0] OUT2[:0] OUT[:0] Description The each channel output of TSM2 is compressed with 2 bits. It has 3 level output information that is low, middle and high. Bit name Reset Function OUT4[:0] 00 Output of channel 4 00: No output 0: low output 0: middle output : high output OUT3[:0] 00 Output of channel 3 00: No output 0: low output 0: middle output : high output OUT2[:0] 00 Output of channel 2 00: No output 0: low output 0: middle output : high output OUT[:0] 00 Output of channel 00: No output 0: low output 0: middle output : high output 25

27 Output2 Channel 5 ~ 8 Output Register Address (hex): h Type: R Bit7 Bit6 Bit5 Bit4 Bit3 Bit2 Bit Bit0 OUT8[:0] OUT7[:0] OUT6[:0] OUT5[:0] Description The each channel output of TSM2 is compressed with 2 bits. It has 3 level output information that is low, middle and high. Bit name Reset Function OUT8[:0] 00 Output of channel 8 00: No output 0: low output 0: middle output : high output OUT7[:0] 00 Output of channel 7 00: No output 0: low output 0: middle output : high output OUT6[:0] 00 Output of channel 6 00: No output 0: low output 0: middle output : high output OUT5[:0] 00 Output of channel 5 00: No output 0: low output 0: middle output : high output 26

28 Output3 Channel 9~ 2 Output Register Address (hex): 2h Type: R Bit7 Bit6 Bit5 Bit4 Bit3 Bit2 Bit Bit0 OUT2[:0] OUT[:0] OUT0[:0] OUT9[:0] Description The each channel output of TSM2 is compressed with 2 bits. It has 3 level output information that is low, middle and high. Bit name Reset Function OUT2[:0] 00 Output of channel 2 00: No output 0: low output 0: middle output : high output OUT[:0] 00 Output of channel 00: No output 0: low output 0: middle output : high output OUT0[:0] 00 Output of channel 0 00: No output 0: low output 0: middle output : high output OUT9[:0] 00 Output of channel 9 00: No output 0: low output 0: middle output : high output 27

29 9 Recommended TSM2 Initialize Flow (Example) START Power ON H/W Reset Ch On Micom On Ctrl2 Setting : 0x0F Ctrl2 Setting : 0x07 Sensitivity Setting? Yes No Sensitivity Setting Ch ~ CH2 Ctrl Setting? Yes No Channel_Hold Off Ch ~ CH2 Ctrl Setting Reset Off CH ~ CH2 END 28

30 0 Recommended Circuit Diagram 0. Application Example in clean power environment T4 T3 T2 T 0 RSYNC 2M R_SB 2M T5 T6 T7 T8 T9 R_B 50K N.C. C_B 820p RBias SRBIAS CS5 CS6 CS7 CS8 CS9 N.C. CS4 CS0 CS3 CS2 CS ADS TSM2 SYNC/OPT CS CS2 VSS N.C. VSS IRBIAS P_CDEG2 RST P_CDEG P_CDEG0 ID_SEL I2C_EN INT SDA SCL OUT RO2 0K OUT SCL RO3 0K SDA RO4 0K INT RO 0K RO5 0K EN 0 I2C_EN INT SDA SCL OUT C_ u RST RST 0 T0 N.C. 0 0 T T2 TSM2 Application Example Circuit (Clean power environment) R_IB 20k In PCB layout, R_B should not be placed on touch pattern. If not, C_B has to be connected. The R_B pattern should be routed as short as possible. The CS patterns also should be routed as short as possible and the width of line might be about 0.25mm. The capacitor that is between and GND is an obligation. It should be located as close as possible from TSM2. The CS pattern routing should be formed by bottom metal (opposite metal of touch PAD). The empty space of PCB must be filled with GND pattern to strengthen GND pattern and to prevent external noise from interfere with sensing frequency. The TSM2 is reset if RST Pin is high. (See 6.5 Reset implementation chapter) The TSM2 is working with single output mode if the SYNC/OPT pin is high and it will be in multi output mode when it s low. The resistor which is connected with GND should be connected with SYNC pin when the application is required over two TSM2 devices (Multi output mode).. 29

31 0.2 Application Example in noisy environment T4 T3 T2 T CS2 0p T5 T6 T7 T8 T9 RS5 200 RS6 200 RS7 200 RS8 200 RS CS9 0p 0 RO2 0K OUT SCL SDA RO4 0K RO5 0K I2C_EN INT SDA SCL OUT RST RST CS2 0p 0 RS4 RS3 RS2 RS CS 0p 0 CS3 0p CS4 0p RSYNC 2M CS8 0p R_SB 2M CS7 CS6 0p 0p R_B 50K CS5 0p N.C. C_B 820p RBias SRBIAS CS5 CS6 CS7 CS8 CS9 N.C. CS4 CS0 ADS TSM RO3 0K 0 C_ u CS 0p CS0 0p RS 200 RS2 200 CS3 CS2 CS SYNC/OPT CS CS2 VSS N.C. VSS IRBIAS P_CDEG2 RST P_CDEG P_CDEG0 ID_SEL I2C_EN INT SDA SCL OUT INT RO 0K EN N.C. 5 6 R_IB 20k RS0 200 T0 T T2 TSM2 Application Example Circuit (Noisy environment) The periodic voltage ripple over 50mV and the ripple frequency is lower than 0 khz can cause wrong sensitivity calibration. To prevent above problem, power (, GND) line of touch circuit should be separated from other circuit. Especially LED driver power line or digital switching circuit power line certainly should be treated to be separated from touch circuit. The smaller R_B is recommended in noisy environments. 30

32 0.3 Example Power Line Split Strategy PCB Layout A. Not split power Line (Bad power line design) The noise that is generated by AC load or relay can be loaded at 5V power line. A big inductance might be appeared in case of the connection line between main board and display board is too long, moreover the voltage ripple could be generated by LED (LCD) display driver at (5V). B. Split power Line (One 5V regulator used) Recommended C. Split power Line (Separated 5V regulator used) Strongly recommended 3

33 MECHANICAL DRAWING 32

34 NOTE: Dimensions are in millimeters 2 MARKING DESCRIPTION Device Code : T S M 2 Weekly Code : YY ZZ Channel Number Application Touch Switch Group Manufacturing Year Manufacturing Week 33

35